Motor Support Device For Heating, Ventilation and/or Air-Conditioning System

ABSTRACT

The invention relates to a support device ( 1 ) of a motor of a blower. The support device ( 1 ) comprises a base ( 2 ), a ring ( 3 ) which extends according to an axis (A) and which is able to house the motor. The support device ( 1 ) also comprises at least a decoupling means ( 4 ) which connects the base ( 2 ) and the ring ( 3 ). The base ( 2 ) comprises a first face ( 11 ) extending according to the axis (A) and the ring ( 3 ) comprises a second face ( 12 ) extending according to the axis (A). The decoupling means ( 4 ) is interposed between the first ( 11 ) and the second ( 12 ) face. 
     The decoupling means has an “H” specific shape in order to absorb the vibrations caused by the motor.

This invention relates to the field of motor support devices for motor vehicle heating, ventilation and/or air-conditioning systems. More specifically, the invention relates to a support device including means for decoupling motor vibrations.

In a heating, ventilation and/or air-conditioning system, the air flow circulating in it is propelled by a blower wheel driven in rotation by a motor. The implementation of the blower wheel and the motor create vibrations. These vibrations are the source of sound and vibration (imbalance) disturbances, in the vehicle interior, of the motor housed in a motor support. The vibrations are transmitted via the motor support to the entire heating, ventilation and/or air-conditioning system and create acoustic waves that interfere with the comfort of vehicle passengers.

To overcome this, decoupling means have been provided between the motor and the motor support or between a ring housing the motor and the motor support. These decoupling means are effective only for a certain type of vibrations and do not enable the transmission of any type of vibrations to the heating, ventilation and/or air-conditioning system to be prevented. However, when an motor drives a blower wheel, a number of phenomena add up and cause a multitude of different vibrations. First, the imbalance of the wheel causes a radial movement of the motor that should be avoided. Second, a “pumping” phenomenon due to the suction of air by the blower wheel as well as the deformation of the wheel causes an axial movement of the motor. Finally, as the motor drives the blower wheel by rotation, a pitching movement or so-called tangential movement of the motor is created. Moreover, depending on the position of the motor in the heating, ventilation and/or air-conditioning system, i.e. depending on the horizontal or vertical position of the motor shaft, the phenomena mentioned above are more or less intense. Consequently, a choice is made regarding the type of vibration dealt with by the decoupling means. An example is document U.S. Pat. No. 6,279,866. This document presents two embodiments. The first embodiment involves decoupling of the motor from the motor support for radial vibrations of the motor. The other embodiment involves decoupling the motor from the motor support for axial vibrations of the motor.

This is not satisfactory from the perspective of standardization of the decoupling means used or from the perspective of its location in the motor support device. The decoupling means of the prior art are not suitable for decoupling the motor from the motor support regardless of the position of the motor, i.e. whether the motor is in the horizontal or the vertical position. Moreover, not all of the sound disturbances created by this multitude of vibrations are dealt with. The comfort of passengers in the vehicle is therefore not optimal.

The invention is intended to improve this situation.

To do this, the invention relates to a motor support device including a base, a ring extending according to an axis A and capable of housing a motor with an axis A and at least one decoupling means connecting the base and the ring, in which said ring has a first face that extends according to axis A, and said base has a second face that extends according to axis A. The decoupling means are interposed between the first and the second faces.

Other features of the invention are listed below:

-   -   the decoupling means are a parallelepiped contact including a         first side in direct contact with the ring, a second side in         direct contact with the base and a third free side extending in         an axial plane with respect to the axis A of the motor, in which         the third side has at least one recess extending in a direction         parallel to the axis A.     -   the decoupling means include a fourth side having at least one         recess. The specific structure of the decoupling means ensure         the decoupling between the motor and the motor support         regardless of the type of vibrations caused by implementation of         the motor and the blower wheel. Thus, the axial and tangential         vibrations are absorbed by the decoupling means. In this way, a         very clear improvement in the comfort of vehicle passengers is         achieved since none of the sound disturbances are created any         longer. The recess created in a direction parallel to the axis A         causes a flexibility of the contact with respect to an axial         constraint and a tangential constraint while maintaining the         rigidity of the contact with respect to a radial constraint. An         advantage of this particular structure is that it overcomes the         loss in damping properties of the material used for the         decoupling means at low temperature.     -   the decoupling means have an H shape.     -   at least two decoupling means are distributed according to at         least two distinct radial planes.     -   the radial planes are located one with respect to the other so         that the center of gravity of the motor is located between the         radial planes. Thus, the motor can be arranged in the heating,         ventilation and/or air-conditioning system in a horizontal or a         vertical position. The particular arrangement of the radial         planes standardizes the support device, leading to a reduction         in production costs.     -   each decoupling means of a first radial plane is offset by an         angle of between 0 and 120° with respect to decoupling means of         a second radial plane.     -   each radial plane includes three decoupling means distributed         with an angular offset of 120°. The particular distribution of         the decoupling means involves a uniformity of the forces exerted         on the decoupling means. In this way, the damping or attenuation         of the vibrations created by the motor during implementation         thereof is optimal.     -   it includes six decoupling means.     -   a hood is associated with the base in order to form a motor         support.     -   the hood and the base are made in one piece.     -   the base, the ring and the decoupling means form a single part.     -   the part is plastic.

The invention also relates to a process for producing the support device including the following steps:

a) molding the ring and the base with a first plastic material

b) over-molding the decoupling means with a second plastic material.

Other features and advantages of the invention will appear on examination of the following detailed description, and the appended drawings, in which:

FIG. 1 is a top view of the support device according to a first embodiment,

FIG. 1 a is a perspective view of the decoupling means according to the invention,

FIG. 2 a is a perspective view of the ring equipped with decoupling means according to the first embodiment of the invention,

FIG. 2 b is a top view of FIG. 2 a,

FIG. 3 is a perspective view of the ring 3 according to the invention,

FIG. 4 is a perspective view of the base 2 according to the first embodiment,

FIG. 4 a is a partial cross-section view of the base 2 of FIG. 4,

FIG. 5 is a side view of the motor support according to the first embodiment.

The appended drawings may serve not only as a complement to the invention, but also contribute to its definition, where appropriate.

FIG. 1 shows the support device 1 according to a first embodiment. The support device 1 includes a base 2, a ring 3 and decoupling means 4.

The ring 3 is a hollow cylinder. It extends according to an axis A and is capable of housing a motor with an axis A. By “extend”, we mean that the length of the cylinder has a direction parallel to that of the axis A. The motor, not shown, causes the rotation, during implementation, of a blower wheel housed in a housing. This blower wheel creates an air flow passing through the heating, ventilation and/or air-conditioning system.

The ring 3 has a first face 5 that extends according to the axis A. This first face 5 is the external face of the hollow cylinder. A first end 6 of the ring 3 is open and includes three shoulders 7. These shoulders 7 extend the first end 7 in a radial direction with respect to the axis A. A second open end 8, opposite the first end 7, includes three flexible tabs 9. The shoulders 7 and the flexible tabs 9 keep the motor with the axis A inside the ring 3.

The base 2 is a hollow cylinder of which the ends are open. The hollow cylinder extends according to the axis A and has a second face 10 that extends according to this axis A. This second face 10 is the internal face of the base 2.

The ring 3 is located inside the base 2 so that the first face 5 of the ring 3 is opposite the second face 10 of the base 2. Nevertheless, the ring 3 and the base 2 are not in direct contact. The ring 3 is kept inside the base 2 by the decoupling means 4.

The decoupling means 4 are contacts. The decoupling means are interposed between the first face 5 of the ring 3 and the second face 10 of the base 2. Each contact 4 has a parallelepiped shape. By “parallelepiped”, we mean a hexahedron of which the sides are parallelograms, with the opposite sides being parallel and equal. Each contact 4 therefore has a first side 11 in direct contact with the first face 5 of the ring 3 and a second side 12 in direct contact with the second face 10 of the base 2. Each contact 4 also includes a third free side 13 extending in an axial plane with respect to the axis A. This third free side 13 has at least one recess 15 extending in a direction parallel to the axis A. By “free”, we mean that the third side is not in contact with the ring 3 or the base 3. By “axial plane”, we mean any plane containing the axis A. A fourth side 14, opposite the third side 13, includes at least one recess 15 extending in a direction parallel to the axis A. It should be noted that the first 11, the second 12, the third 13 and the fourth 14 sides extend in a direction parallel to the axis A.

These decoupling means 4 ensure the decoupling between the motor, not shown, capable of being housed in the ring 3 and the base 2. More generally, the decoupling means 4 ensure the decoupling between the motor and the heating, ventilation and/or air-conditioning system in which it is integrated.

The decoupling means 4 are made of plastic material. More specifically, the decoupling means 4 re made of a damping material. By “damping”, we mean that the plastic material absorbs the vibrations of the motor so as not to transmit them to the base. An example of a damping material is natural rubber. The recess 15 formed on the third side 13 and the fourth side 14 gives the contact an H shape from a top view of the support device (FIG. 1). This H shape ensures a decoupling of the motor according to at least three distinct movements.

In FIG. 1 a, the decoupling means 14 are shown alone. The contact 4 has a length L, a length I and a thickness E. The third side 13 and the fourth side 14 each have a recess 15. The contact 4 also includes a fifth side 19 and a sixth side 20. The fifth 19 and sixth 20 sides are free and opposite one another. Each recess 15 extends according to the axis A over the entire length of the side on which it is formed. Thus, each recess 15 ends both at the fifth side 19 and at the sixth side 20, giving the contact 4 and H shape from a view parallel to the axis A. In this case, the recess 15 is in the form of a U-shaped groove. Alternatively, a V-shape can be envisaged. The presence of the two recesses 15 forms a trunk 21. This trunk 21 is the portion of the contact 4 that is stressed in order to ensure the decoupling between the motor and the base 2. Indeed, as described below, the first side 11 and the second side 12 of the contact 4 are surrounded by ribs 16 and ridges 17. These ribs 16 form a cradle 23 for each contact 4. Thus, only the trunk 21 of each contact can be deformed when the motor and the blower wheel are implemented. The dimensions of the recesses 15 are chosen so that the trunk can decouple the motor from the base 2. Thus, the thicker the contact 4 is, the more the recesses 15 are superficial. In other words, the width of the trunk 21 is greater than or equal to 20% of the width 1 of the contact 4. Similarly, the thickness of the trunk 21 is greater than or equal to 20% of the thickness E of the contact 4. A notch 22 is formed on the first side 11 of the contact 4. This notch 22 cooperates with a rib 16 when the contact 4 is over-molded on the ring 3. The rib cooperating with the notch 22 increases the contact surface between the first side 11 and the first face 5 of the ring 3 in order to reinforce the mechanical connection between the contact 4 and the ring 3.

The first movement caused by the implementation of the motor and the blower wheel is an axial movement MA. By “axial movement”, we mean a movement in a direction parallel to the axis A. This axial movement is more specifically a so-called pumping movement caused by the rotation o the blower wheel. The trunk 21 of each contact 4 is deformed in a direction parallel to the axis A in order to attenuate this movement. The second movement is a radial movement MR. By “radial movement”, we mean a movement in a radial direction with respect to the axis A. The trunk 21 is then compressed and/or decompressed according to its thickness in order to prevent the transmission of this movement to the base 2. The third movement is a tangential movement MT. By “tangential movement”, we mean a rotation movement with respect to the axis A. The trunk 21 is also subjected to this movement and is deformed in a clockwise and/or counterclockwise direction with respect to the axis A. Consequently, the decoupling means 4 enables three-dimensional decoupling of the ring 3 subjected to the movements of the motor with respect to the base 2.

FIGS. 2 a and 2 b show the ring 3 equipped with decoupling means 4. There are six decoupling means 4 in the first embodiment. Among the six contacts 4, at least two contacts 4 are distributed according to a first radial plane P1 and at least two contacts 4 are distributed according to a second radial plane P2. By “radial plane”, we mean any plane orthogonal to the axis A and extending in a radial direction with respect to the axis A. As the first radial plane P1 is distinct from the second radial plane P2, the distribution of the plurality of contacts forms at least two rows of contacts. According to FIG. 2 a, three contacts 4 are distributed according to the first radial plane P1 and the three other contacts are distributed according to the second radial plane P2.

The position of the radial planes P1 and P2 is chosen so that the center of gravity G of the motor, not shown, is between these two radial planes P1 and P2. Thus, regardless of the position of use of the motor, the motor is always held correctly in the base 2. In other words, whether the axis A of the motor is in the horizontal or the vertical position, the distribution of contacts 4 ensures that the motor is held in the base 2. The presence of six contacts 4 and the distribution of these contacts help to improve the standardization of the support device. Indeed, when a support device of the prior art includes only three decoupling contacts, the center of gravity of the motor can, when the axis A of the motor is in the horizontal position, cause a force on a portion of the motor that is not opposed. In this way, the axis of the motor can be tilted with respect to the horizontal, which would cause friction of the blower wheel on the internal wall of the housing containing it. Moreover, it is advantageous to arrange the radial planes P1 and P2 at the ends of the ring 3. In this way, regardless of the motor housed in the ring 3, its center of gravity G will be between these two radial planes. Thus, a single ring 3 equipped with contacts 4 distributed according to the two radial planes P1 and P2 located at the ends of the ring 3 can be used with motors of identical size but having their center of gravity G located differently. The standardization of the support device 1 is thus improved.

The three contacts distributed according to the same radial plane are offset from one another by an angle α of 120° with respect to the axis A. This distribution of contacts of the same radial plane enables a static and dynamic balance of the motor in the planes parallel to the axis A. In general, the angular offset α is determined by the following ration: α=360/(number of contacts distributed in the same radial plane).

According to the first embodiment, each contact 4 is offset from the adjacent contact by an angle β of 600. This distribution is an improvement with regard to the balance in the plane perpendicular to the axis of the motor. By “adjacent contact”, we mean the contact that follows a preceding contact along the first face 5 of the ring 3. In general, each decoupling means 4 of a first radial plane P1 is offset by an angle β of between 0 and 120° with respect to a decoupling means 4 of a second radial plane P2.

FIG. 3 shows the ring 3 alone. The ribs 16 of the ring 3 surrounding the first side 11 of each contact 4 are arranged on the first face 5 of the ring 3. The ribs 16 form cradles 23. A cradle 23 is shaped so as to receive the first side 11 of a contact 4. Four ribs 16 define a cradle 23 so that it has a rectangular shape. An additional rib 16 is located at the center of the cradle 23. This additional rib 16 cooperates with the notch 22 of the contact 4 so as to reinforce the mechanical strength between the first side 11 of the contact and the first face 5 of the ring 3. The cradles formed by the ribs are involved in the over-molding of the contacts 4. The process for producing the support device 1 will be described below.

According to a first embodiment, the ring 3 and the contacts 4 are made in one piece. By “in one piece”, we mean that the ring 3 and the contacts 4 form a single part 26. In this embodiment, the support device 1 is formed by the assembly of the base 2 to the single part 26 by means of the contacts 4. According to FIG. 4, on the second face 10 of the base 2, ridges 17 are provided. These ridges 17 partially surround the second side 12 of the contacts 4 in direct contact with the second face 10. The ridges 17 form housings 24. Each housing 24 is shaped so as to receive the second side 12 of a contact 4. More specifically, each housing 24 is formed by three ridges 17. Thus, one side of the housing is free, i.e. one side of the housing 24 does not have a ridge so that it can introduce the second side of the contact 4. The ridges 17 forming a housing 24 are arranged so that the housing 24 has a trapezoid shape. Thus, when the second side 12 of a contact is inserted into the housing 24, the trapezoid shape ensures an easy insertion of the second side 12 into the housing 24. Of course, according to this embodiment, the second side of the contact 4 has a trapezoid shape so as to cooperate with the housing. The correspondence in shape between the housing 24 and the second side enables both ease of assembly and attachment of the single part 26 with the base 2. Moreover, according to FIG. 4 a, each ridge 17 has a collar 25. The ridge 17 thus has an L shape. When the base 2 is assembled on the single part 26, each second side 12 of the contacts 4 penetrates a housing 24. The shape cooperation between the second side 12 and the collar 25 of each ridge 17 keeps the contacts 4 in their housing 24. In other words, the contacts 4 are inserted by sliding into the housings 24, and the collars 25 radially hold the contacts 4 against the base 2.

FIG. 5 shows the base 2 and a hood 18. The base 2 and the hood 18 of the base 2 form a motor support 27. The hood 18 is a bowl that contains one end of the base 2. The hood 18 comprises at least one tab 28 cooperating with a lug 29 arranged on the base 2. The tab 28 and the lug 29 form means for attachment between the base 2 and the hood 18. The fact that the motor support 27 is in two distinct parts enables the motor to be balanced. In this sense, when the support device 1 is formed, namely when the base 2 is attached to the single part 26, the motor is inserted into the ring 3 and is held inside it by means of shoulders 7 and flexible tabs 9. Then, the motor is installed and is held in a testing bench by its base. The holding of the motor by its base enables the blower wheel to be forced onto the motor shaft. Thus, the support device 1 is not subjected to the forces exerted on the blower wheel and on the motor for the assembly of this wheel. No damage to the support device can occur while it is housing the motor. Finally, the blower wheel is balanced. For this, then motor is implemented and drives the blower wheel. The fact that the base 2 is open and that the motor is held by its bottom in the testing bench means that the support device is not involved in the tests. In this way, the balancing of the blower wheel is not disrupted by the support device including the decoupling means.

According to a second embodiment, not shown, the support device 1 is obtained according to a single molding process. First, the ring 3 and the base 2 are formed by molding a first plastic material. Then, the contacts 4 are over-molded both on the base 2 and the ring 3. The contacts 4 are preferably obtained with a second plastic material, distinct from the first plastic material. In this embodiment, the attachment means formed by the lug 29 and the tab 28 are no longer present on the base 2 and the ring 3, respectively. However, the advantage obtained by the opening of the base 2 in order to attach the motor by its bottom in a testing bench remains present. In addition, the ridges 17 forming a housing 24 entirely surround the second side 12 of the associated contact 4 since it is no longer necessary to insert the second side into said housing 24. It should be noted that this production process is described as “one shot”. In other words, this process enables, by using a single molding apparatus, the support device to be obtained in which the base, the ring and the decoupling means form a single part. More specifically, the molding of the base and the ring is performed in the same mold using a first plastic material. Then, a second plastic material is introduced into the same mold in order to form the decoupling means. The decoupling means are then over-molded on the base and the ring, and the latter are still present in the mold during the over-molding of the decoupling means. In this embodiment, the ridges 17 orient the second plastic material toward the housings 24 during the over-molding of the decoupling means. In addition, the trapezoid shape of the housings 24 improves the ease of molding of the contacts 4.

According to a third embodiment, not shown, the motor support 27 is made in one piece. Thus, when the motor is housed in the ring 3 equipped with these contacts 4, said contacts are inserted into the housings 24 from the base 2 forming a single part with the hood 18. In this embodiment, the performance tests on the motor are performed before the support device 1 is placed on the motor.

According to a fourth embodiment, not shown, the support device 1 is capable of housing a two-wheel motor. In this case, the base 2 alone forms the motor support and includes means for attaching said support device to the heating, ventilation and/or air-conditioning system.

According to another alternative of the invention, the decoupling means include a single recess 15 on the third side 13. In other words, the fourth side 14 has a planar surface. The contact 4 then has a U shape.

Regardless of the embodiment or alternative envisaged, the following features apply.

The base 2 is formed by a first plastic material. Preferably, the first plastic material is polypropylene. The ring 3 is also formed by this first plastic material.

The decoupling means 4 in the form of a contact 4 are formed by a second plastic material. This second plastic material is natural rubber, polypropylene, EPDM or SEBS. It should be noted that the H shape of the decoupling means 4 enable polypropylene for example to be used as the second plastic material. Indeed, even though polypropylene does not have good elastic properties compared with those of natural rubber, it can be used to form the decoupling means 4 since the recesses 15 on the third 13 and fourth 14 sides involve flexibility of the decoupling means at the level of the trunk 21.

In addition, the H shape of the decoupling means enable the loss in elastic properties to be overcome when the temperature of the second plastic material is low, for example below 0° C. Thus, when a motor vehicle including a heating, ventilation and/or air-conditioning system equipped with a support device according to the invention is used during the winter, the H shape helps to ensure the three-dimensional decoupling of the motor from the motor support. 

1. A motor support device (1), including a base (2), a ring (3) extending according to an axis (A) and capable of housing a motor with an axis (A) and at least one decoupling means (4) connecting said base (2) and said ring (3), in which said ring (3) has a first face (5) that extends according to the axis (A), and said base (2) has a second face (10) that extends according to the axis (A), characterized in that said decoupling means (4) are interposed between the first (5) and the second (10) faces.
 2. A support device (1) according to claim 1, in which said decoupling means (4) are a parallelepiped contact including a first side (11) in direct contact with said ring (3), a second side (12) in direct contact with said base (2) and a third free side (13) extending in an axial plane with respect to the axis (A) of the motor, in which said third side (13) has at least one recess (15) extending in a direction parallel to the axis (A).
 3. A support device (1) according to claim 2, in which said decoupling means (4) include a fourth side (14) having at least one recess (15).
 4. A support device (1) according to claim 1, in which said decoupling means (4) have an H shape.
 5. A support device (1) according to claim 1, in which at least two decoupling means (4) are distributed according to at least two distinct radial planes (P1, P2).
 6. A support device (1) according to claim 5, in which the radial planes (P1, P2) are located one with respect to the other so that the center of gravity (G) of the motor is located between the radial planes (P1, P2).
 7. A support device (1) according to claim 4, in which each of said decoupling means (4) of a first radial plane (P1) is offset by an angle (β) of between 0 and 120° with respect to decoupling means (4) of a second radial plane (P2).
 8. A support device (1) according to claim 4, in which each radial plane (P1, P2) includes three decoupling means (4) distributed with an angular offset (α) of 120°.
 9. A support device (1) according to claim 1, including six decoupling means (4).
 10. A support device (1) according to claim 1, in which a hood (18) is associated with said base (2) in order to form a motor support (27).
 11. A support device (1) according to claim 10, in which said hood (18) and said base are made in one piece.
 12. A support device (1) according to claim 1, in which said base (2), said ring (3) and said decoupling means (4) form a single part.
 13. A support device (1) according to claim 12, which is plastic.
 14. A process for producing the support device according to claim 12, said process comprising the following steps: a) molding the ring and the base with a first plastic material, and b) over-molding the decoupling means with a second plastic material.
 15. A support device (1) according to claim 2, in which said decoupling means (4) have an H shape.
 16. A support device (1) according to claim 2, in which at least two decoupling means (4) are distributed according to at least two distinct radial planes (P1, P2).
 17. A support device (1) according to claim 5, in which each of said decoupling means (4) of a first radial plane (P1) is offset by an angle β of between 0 and 120° with respect to decoupling means (4) of a second radial plane (P2). 